POST-MORTEM EXAMINATION OF INFECTED ANIMALS. 279 



after death, before: coagulation has set in. This can be easily 

 accomplished in the following- manner: With sterile scissors 

 the pericardial sac should be opened and the heart exposed. 

 The apex of the heart is grasped in a pair of broad pointed 

 forceps, preferably arterial forceps, and the surface of the 

 heart is burned with a red-hot glass rod or searing iron 

 (Pig. 48). The point of a sterile, drawn out tube pipette, 

 is then broken or cut off. The end of the pipette is steril- 

 ized by passing through the flame several times, and, when 

 cool, it is passed through the burned surface into the right 

 ventricle. The heart should be held on a stretch. Suction 

 is now applied to the mouth of the pipette, and the blood 

 is thus drawn up into the tube. The culture media can be 

 inoculated direct by means of the pipette, or the latter may 

 be sealed and the contents thus preserved. It may be inci- 

 dentally remarked that the organisms thus kept in blood 

 preserve their vitality and virulence for a greater length of 

 time than on ordinary media. 



In many instances, it is desirable to examine the mu- 

 cous membrane of the stomach and intestines for hemor- 

 rhagic infiltrations and necroses. The digestive tube in 

 that case should be slit up longitudinally and washed, pre- 

 ferably in a dilute formaldehyde or in mercuric chloride 

 solution. 



Cover-glass preparations should be made from the 

 peritoneal surface of the abdominal wall, or from the sur. 

 face of the intestines, liver, lungs, etc. These are easily 

 prepared by placing the clean cover-glass on the selected 

 surface, and then drawing it off by means of a pair of for- 

 jceps. A thin layer of material adheres to the cover-glass. 



Similar preparations should be made from the cut sur- 

 faces of the various organs. For this purpose, the cover- 

 glasses are placed on a mounting board' and held in place 



1 Two boards are supplied. The large one is 25 cm. square; the 

 other li X 20 cm. 



